Regulations on a Solar Power System

Figure 6: String Ribbon Manufacturing Process12
http://docs.google.com/File?id=dfd49hhc_5hsjq9mgk_b12 Evergreen Solar, Inc. (2008). String Ribbon. Retrieved October, 2008, from http://evergreensolar.com/images/techology/stringribbon/diagram_string_ribbon_en.jpg
13 Evergreen Solar, Inc. (2008). Our String Ribbon Wafers - Genius in its Simplicity. Retrieved October, 2008, from http://www.evergreensolar.com/app/en/technology/item/48
The result of this process is a thin, silicon ribbon, which is twice the yield of the conventional construction per pound of silicon. Due to this fact, String Ribbon panels use significantly less material than crystalline panels. The process of creating String Ribbon panels achieves a much greater reliability and potency than its silicon wafer counterpart and manufacturing it is one of the most environmentally friendly methods in the business.13
Thin-film Panels
With advent of micro-manufacturing, many large scale photovoltaic panels are becoming smaller and smaller with each progressive decade. The ability to spread a material over a large scale area that averages 1 to 10 micrometers thick has enabled several manufactures to produce an ultra thin variety of solar panels. This newly emerging technology is aptly named: thin-film technology. Thin-film
technology refers to the act of spreading several consecutive layers of silicon and other material to form a working photovoltaic. Thin-film material is 100 times thinner than traditional solar panels, which range from 100 to 300 micrometers thick, and only contains 1% of the silicon to produce an equivalently sized panel.14 The greatest advantages of thin-film technology are that it is flexible, light weight, and incredibly thin. Unlike silicon wafers and String Ribbon panels, many thin-film panels are created as an amorphous material. Instead of being manufactured in chunks and assembled into a panel like String Ribbon panels and silicon wafer panels, thin-film panels are created by combining consecutive thin layers of material together. The result is a single film that is capable of being distributed in rolls or sheets. 15
http://docs.google.com/File?id=dfd49hhc_13cvnqfmfz_b14 PowerFilm, Inc. (2008). Thin Film. Retrieved October, 2008, from http://www.powerfilmsolar.com/technology/index.html 15 Quaschning, Volkerr. Understanding Renewable Energy Sources. London : Earthscan, 2005.

Figure 7: Thin-film Composition
Today, many thin-film manufacturers have begun producing what is referred to as monolithic integration. Monolithic integration describes the process of integrating the connection junctions between the silicon substrates, which create paths for the electricity to flow from cell to cell, within the amorphous material. This process is can be referred to as the "All-in-one" technique. Because of the character of thin-film material, manufacturers have been able to integrate these connection junctions with such success that many are capable of tolerating a bullet hole without failing. Some are also capable of performing better than traditional silicon wafer panels under low light or shaded
conditions. Monolithic integration reduces manufacturing costs and increases durability of the overall product.
While thin-film technology receives much praise, it does have several drawbacks. Because of its thin nature, thin-film material generally has a lower efficiency compared to its silicon wafer competitor. In consequence, more area must be dedicated to a thin-film panel to produce the same result as a silicon wafer panel of equal power rating. Another disadvantage of a thin material is that durability begins to suffer over time. Thin film solar panels degrade more quickly than other types of technologies which make them candidates for a more frequent replacement.16
16 U.S. Department of Energy. (2006). Polycrystalline Thin Film. Retrieved October, 2008, from http://www1.eere.energy.gov/solar/tf_polycrystalline.html
2.3 Regulations and Installation
There are several rules and regulations in effect that apply to solar array purchasers. Knowing them can not only protect your well being but also save you money. The Massachusetts Technology Collaborative (MTC) provides a wealth of information about the type of funds and rebates available to those interested in installing solar panel arrays on their business or residence. MTC also provides a list of tasks that must be fulfilled before a solar array may be deemed operational and hazard free.
2.3.1 How Solar Panels are Installed
The installation of most roof based solar arrays is a relatively simple process. The primary method involves attaching bolts to the roof support beams, through the roof surface and building a simple framework on top of these bolts to allow a gap between the panels and the roof surface. This gap permits the panels to be installed on roof surfaces ranging from rubber membranes, standard asphalt
shingles, tiles, and slate, even if the roof is somewhat uneven. The gap also allows for airflow to keep the panels cool. The most common way to install panels on a flat roof, like the Wesley Church’s, is to purchase separate frames that assemble into some sort of “A” frame. The panels can be mounted vertically or horizontally with approximately four panels per frame. This frame is then either bolted through the roof into the rafters below, or weighted down with sandbags or something similar. These mounting frames can either be situated at a fixed angle or one that can be adjusted to two or three pre-set angles and locked with removable pins. The adjustment process can be done with two people and increases the efficiency of the cells, while only slightly complicating the mounting frames. On the church roof, several lines of these frames could be assembled with enough space in between to prevent shading from the row in front. Based on the sun’s effect at various times of the day, different groups would be connected in series and then in parallel to the DC/AC converter. These rows should also be spaced in such a way that the roof is still accessible for regular maintenance. While it is possible for homeowners to install several systems themselves, such as the Schott Sunroof PV system, it is generally recommended that one work with a professional contractor. Not only are contractors experienced in installation procedures, they are also familiar with the available rebates and other incentives. Most importantly, the contractor will coordinate with a licensed electrician to make the connections to the breaker panel and request an electrical inspection from the town to ensure that all procedures are up to code.
2.3.2 Regulations on a Solar Power System
In order to ensure the safety of a solar power system, the system must conform to a number of federal, state, and local regulations. In particular, Commonwealth Solar, an organization that offers rebates to individuals or groups wishing to install a solar panel system, outlines a number of criteria that
a solar panel system must meet in order to receive a rebate. These criteria go beyond simple safety measures to include requirements on the life and overall quality of the system.17 Many of the safety regulations for solar panel installations regard the electrical safety of the system. A system installed in Massachusetts must be installed by a licensed electrician, and conform to all federal, state, and local electric and building codes. Wiring must be properly insulated and weatherproofed. Devices that can be disconnected from the rest of the electrical system for service and inspection must also be installed. Although it is not required, the MTC recommends that surge protectors are installed to protect the system components from any electrical surges.
17 Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
18 Commonwealth Solar. Overview. Retrieved September, 2008, from http://www.masstech.org/SOLAR/
2.4 Economics
2.4.1 Incentives Available to System Buyers
Because of the increasing demand for renewable energies, a number of organizations have been created to foster the growth of systems that utilize renewable sources. Both public and private institutions can benefit from the incentives that such organizations provide. When determining the feasibility of a solar power system, it is important to consider the economic incentives that may apply, because they may account for a considerable portion of the system cost.
Commonwealth Solar is an initiative from the Massachusetts Technology Collaborative (MTC) to provide rebates to residential, commercial, industrial, and public facilities. Commonwealth Solar provides rebates on photovoltaic systems on a non-competitive, first-come, first-serve basis. Starting in 2008, the initiative has $68 million available over the next four years.18 The amount of reimbursement that an installation may receive depends on the size of the installation (in kW), whether the components
of the system were manufactured in Massachusetts, and whether the installation is on a public or private building. The rebates are calculated in dollars per DC watt of energy produced by the system.
The base rebate per Watt, based on system size, is shown below:19
19 Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
Size of system (kW)
1 to 25 kW
>25 to 100 kW
>100 to 200 kW
>200 to 500 kW
Rebate in dollars per watt
$3.25
$3.00
$2.00
$1.50

Table 1: MTC Rebates
. An additional $0.25 per watt will be added if the components of the system were manufactured in Massachusetts . An additional $1.00 per watt will be added if the system is installed on a public building.
In order to receive a grant from Commonwealth Solar, the system that is to be installed must have a projected efficiency of at least 80% compared to a system under optimal conditions. Commonwealth solar derives these optimal efficiencies from the PVWATTS calculations made by the National Renewable Energy Laboratory. The parameters for optimal installation in Worcester, MA are as follows:
. 77% DC to AC conversion rate . A 42 degree array tilt . A due South orientation of the panels
Applying these parameters to the Worcester area produces a kilowatt per hour price of 11.8 cents with a price of 14.8 cents per kilowatt hour if the system is at 80% for the efficiency of the optimal system. Systems with a projected efficiency less than 80% may still be considered for a rebate, but the amount of the rebate is reduced on a sliding scale with reduced efficiency. Using this scale, systems with efficiencies as low as 65% of optimal may still receive a rebate (70% of the normal rebate with a 65% optimal system). The price per kilowatt hour for a system with 65% of optimal efficiency is 19.7 cents.20 In order to be eligible, the installation must be approved by a Massachusetts licensed electrician. The installation must meet all local, state, and federal building and electrical codes. An Interconnection Agreement must also be filed with the utility company to which the system will interface. The components of the solar system to be installed must have certain minimum warranties in order to qualify, including: http://docs.google.com/File?id=dfd49hhc_5hsjq9mgk_b12 Evergreen Solar, Inc. (2008). String Ribbon. Retrieved October, 2008, from http://evergreensolar.com/images/techology/stringribbon/diagram_string_ribbon_en.jpg
13 Evergreen Solar, Inc. (2008). Our String Ribbon Wafers - Genius in its Simplicity. Retrieved October, 2008, from http://www.evergreensolar.com/app/en/technology/item/48
The result of this process is a thin, silicon ribbon, which is twice the yield of the conventional construction per pound of silicon. Due to this fact, String Ribbon panels use significantly less material than crystalline panels. The process of creating String Ribbon panels achieves a much greater reliability and potency than its silicon wafer counterpart and manufacturing it is one of the most environmentally friendly methods in the business.13
Thin-film Panels
With advent of micro-manufacturing, many large scale photovoltaic panels are becoming smaller and smaller with each progressive decade. The ability to spread a material over a large scale area that averages 1 to 10 micrometers thick has enabled several manufactures to produce an ultra thin variety of solar panels. This newly emerging technology is aptly named: thin-film technology. Thin-film
technology refers to the act of spreading several consecutive layers of silicon and other material to form a working photovoltaic. Thin-film material is 100 times thinner than traditional solar panels, which range from 100 to 300 micrometers thick, and only contains 1% of the silicon to produce an equivalently sized panel.14 The greatest advantages of thin-film technology are that it is flexible, light weight, and incredibly thin. Unlike silicon wafers and String Ribbon panels, many thin-film panels are created as an amorphous material. Instead of being manufactured in chunks and assembled into a panel like String Ribbon panels and silicon wafer panels, thin-film panels are created by combining consecutive thin layers of material together. The result is a single film that is capable of being distributed in rolls or sheets. 15
http://docs.google.com/File?id=dfd49hhc_13cvnqfmfz_b14 PowerFilm, Inc. (2008). Thin Film. Retrieved October, 2008, from http://www.powerfilmsolar.com/technology/index.html 15 Quaschning, Volkerr. Understanding Renewable Energy Sources. London : Earthscan, 2005.

Figure 7: Thin-film Composition
Today, many thin-film manufacturers have begun producing what is referred to as monolithic integration. Monolithic integration describes the process of integrating the connection junctions between the silicon substrates, which create paths for the electricity to flow from cell to cell, within the amorphous material. This process is can be referred to as the "All-in-one" technique. Because of the character of thin-film material, manufacturers have been able to integrate these connection junctions with such success that many are capable of tolerating a bullet hole without failing. Some are also capable of performing better than traditional silicon wafer panels under low light or shaded
conditions. Monolithic integration reduces manufacturing costs and increases durability of the overall product.
While thin-film technology receives much praise, it does have several drawbacks. Because of its thin nature, thin-film material generally has a lower efficiency compared to its silicon wafer competitor. In consequence, more area must be dedicated to a thin-film panel to produce the same result as a silicon wafer panel of equal power rating. Another disadvantage of a thin material is that durability begins to suffer over time. Thin film solar panels degrade more quickly than other types of technologies which make them candidates for a more frequent replacement.16
16 U.S. Department of Energy. (2006). Polycrystalline Thin Film. Retrieved October, 2008, from http://www1.eere.energy.gov/solar/tf_polycrystalline.html
2.3 Regulations and Installation
There are several rules and regulations in effect that apply to solar array purchasers. Knowing them can not only protect your well being but also save you money. The Massachusetts Technology Collaborative (MTC) provides a wealth of information about the type of funds and rebates available to those interested in installing solar panel arrays on their business or residence. MTC also provides a list of tasks that must be fulfilled before a solar array may be deemed operational and hazard free.
2.3.1 How Solar Panels are Installed
The installation of most roof based solar arrays is a relatively simple process. The primary method involves attaching bolts to the roof support beams, through the roof surface and building a simple framework on top of these bolts to allow a gap between the panels and the roof surface. This gap permits the panels to be installed on roof surfaces ranging from rubber membranes, standard asphalt
shingles, tiles, and slate, even if the roof is somewhat uneven. The gap also allows for airflow to keep the panels cool. The most common way to install panels on a flat roof, like the Wesley Church’s, is to purchase separate frames that assemble into some sort of “A” frame. The panels can be mounted vertically or horizontally with approximately four panels per frame. This frame is then either bolted through the roof into the rafters below, or weighted down with sandbags or something similar. These mounting frames can either be situated at a fixed angle or one that can be adjusted to two or three pre-set angles and locked with removable pins. The adjustment process can be done with two people and increases the efficiency of the cells, while only slightly complicating the mounting frames. On the church roof, several lines of these frames could be assembled with enough space in between to prevent shading from the row in front. Based on the sun’s effect at various times of the day, different groups would be connected in series and then in parallel to the DC/AC converter. These rows should also be spaced in such a way that the roof is still accessible for regular maintenance. While it is possible for homeowners to install several systems themselves, such as the Schott Sunroof PV system, it is generally recommended that one work with a professional contractor. Not only are contractors experienced in installation procedures, they are also familiar with the available rebates and other incentives. Most importantly, the contractor will coordinate with a licensed electrician to make the connections to the breaker panel and request an electrical inspection from the town to ensure that all procedures are up to code.
2.3.2 Regulations on a Solar Power System
In order to ensure the safety of a solar power system, the system must conform to a number of federal, state, and local regulations. In particular, Commonwealth Solar, an organization that offers rebates to individuals or groups wishing to install a solar panel system, outlines a number of criteria that
a solar panel system must meet in order to receive a rebate. These criteria go beyond simple safety measures to include requirements on the life and overall quality of the system.17 Many of the safety regulations for solar panel installations regard the electrical safety of the system. A system installed in Massachusetts must be installed by a licensed electrician, and conform to all federal, state, and local electric and building codes. Wiring must be properly insulated and weatherproofed. Devices that can be disconnected from the rest of the electrical system for service and inspection must also be installed. Although it is not required, the MTC recommends that surge protectors are installed to protect the system components from any electrical surges.
17 Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
18 Commonwealth Solar. Overview. Retrieved September, 2008, from http://www.masstech.org/SOLAR/
2.4 Economics
2.4.1 Incentives Available to System Buyers
Because of the increasing demand for renewable energies, a number of organizations have been created to foster the growth of systems that utilize renewable sources. Both public and private institutions can benefit from the incentives that such organizations provide. When determining the feasibility of a solar power system, it is important to consider the economic incentives that may apply, because they may account for a considerable portion of the system cost.
Commonwealth Solar is an initiative from the Massachusetts Technology Collaborative (MTC) to provide rebates to residential, commercial, industrial, and public facilities. Commonwealth Solar provides rebates on photovoltaic systems on a non-competitive, first-come, first-serve basis. Starting in 2008, the initiative has $68 million available over the next four years.18 The amount of reimbursement that an installation may receive depends on the size of the installation (in kW), whether the components
of the system were manufactured in Massachusetts, and whether the installation is on a public or private building. The rebates are calculated in dollars per DC watt of energy produced by the system.
The base rebate per Watt, based on system size, is shown below:19
19 Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
Size of system (kW)
1 to 25 kW
>25 to 100 kW
>100 to 200 kW
>200 to 500 kW
Rebate in dollars per watt
$3.25
$3.00
$2.00
$1.50

Table 1: MTC Rebates
. An additional $0.25 per watt will be added if the components of the system were manufactured in Massachusetts . An additional $1.00 per watt will be added if the system is installed on a public building.
In order to receive a grant from Commonwealth Solar, the system that is to be installed must have a projected efficiency of at least 80% compared to a system under optimal conditions. Commonwealth solar derives these optimal efficiencies from the PVWATTS calculations made by the National Renewable Energy Laboratory. The parameters for optimal installation in Worcester, MA are as follows:
. 77% DC to AC conversion rate . A 42 degree array tilt . A due South orientation of the panels
Applying these parameters to the Worcester area produces a kilowatt per hour price of 11.8 cents with a price of 14.8 cents per kilowatt hour if the system is at 80% for the efficiency of the optimal system. Systems with a projected efficiency less than 80% may still be considered for a rebate, but the amount of the rebate is reduced on a sliding scale with reduced efficiency. Using this scale, systems with efficiencies as low as 65% of optimal may still receive a rebate (70% of the normal rebate with a 65% optimal system). The price per kilowatt hour for a system with 65% of optimal efficiency is 19.7 cents.20 In order to be eligible, the installation must be approved by a Massachusetts licensed electrician. The installation must meet all local, state, and federal building and electrical codes. An Interconnection Agreement must also be filed with the utility company to which the system will interface. The components of the solar system to be installed must have certain minimum warranties in order to qualify, including: